All vehicles from highway trucks to farm wagons have always had the dual problems of suspension systems which are capable of carrying very heavy loads over almost any terrain, and which systems are capable of uniformly distributing the load on the wagon frame to the vehicle supporting means, whether that means be conventional wheels or track systems.
For farm operators, the problem is exacerbated by the need to eliminate as much as practicable the forming of deep ruts in fields used for grain growth and harvesting. Such ruts are usually formed by o combines and heavy grain wagons, in wet and muddy fields. If fields remain deeply rutted into the following spring, crop planting is made tougher because the planter will have to adjust to widely varying terrain in the same field, and soil compaction problems arise from such ruts that could retard plant growth. Further, farmers adopting conservation tillage practices are forced, with deep ruts, to use a light disk or other shallow implement in the following spring to move soil into the ruts while keeping the previous year's residue on the surface.
Many contemporary vehicles do not have suspension systems that will permit the vehicle to maintain a reasonably level attitude when one of the supporting wheels encounters an obstruction or depression. The result is that the vehicle frame and the supporting load are tilted to an undesirable angular position. Additionally, contemporary suspension systems do not distribute the load uniformly creating increasing "pressure peaks" from front to back, as seen for example in tracked vehicles. Further, the castering capability of some suspension systems of today utilizing ground engaging wheels is inadequate to eliminate "herming" which can result from dragging a tracked grain cart or an improperly castered bogie wheel unit through a tight turn.